package com.java.common.utils.file;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.util.Base64;

import org.apache.commons.io.FilenameUtils;
import org.springframework.web.multipart.MultipartFile;

import com.java.common.config.ProjectConfig;
import com.java.common.constant.Constants;
import com.java.common.lang.exception.file.FileNameLengthLimitExceededException;
import com.java.common.lang.exception.file.FileSizeLimitExceededException;
import com.java.common.lang.exception.file.InvalidExtensionException;
import com.java.common.utils.DateUtils;
import com.java.common.utils.StringUtils;
import com.java.common.utils.WebKit;
import com.java.common.utils.uuid.IdUtils;

/**
 * 文件上传工具类
 *
 * @author Administrator
 */
public class FileUploadUtils {

    /**
     * 默认大小 100M
     */
    private static final long DEFAULT_MAX_SIZE = 100 * 1024 * 1024;

    /**
     * 默认的文件名最大长度 100
     */
    private static final int DEFAULT_FILE_NAME_LENGTH = 1000;

    /**
     * 默认上传的地址
     */
    private static String defaultBaseDir = ProjectConfig.getUploadDir();

    public static void setDefaultBaseDir(String defaultBaseDir) {
        FileUploadUtils.defaultBaseDir = defaultBaseDir;
    }

    public static String getDefaultBaseDir() {
        return defaultBaseDir;
    }

    /**
     * 以默认配置进行文件上传
     *
     * @param file 上传的文件
     * @return 文件名称
     * @throws Exception
     */
    public static final String upload(MultipartFile file) throws IOException {
        try {
            return upload(getDefaultBaseDir(), file, MimeTypeUtils.DEFAULT_ALLOWED_EXTENSION);
        } catch (Exception e) {
            throw new IOException(e.getMessage(), e);
        }
    }

    /**
     * 根据文件路径上传
     *
     * @param baseDir 相对应用的基目录
     * @param file    上传的文件
     * @return 文件名称
     * @throws IOException
     */
    public static final String upload(String baseDir, MultipartFile file) throws IOException {
        try {
            return upload(baseDir, file, MimeTypeUtils.DEFAULT_ALLOWED_EXTENSION);
        } catch (Exception e) {
            throw new IOException(e.getMessage(), e);
        }
    }

    /**
     * 文件上传
     *
     * @param baseDir          相对应用的基目录
     * @param file             上传的文件
     * @param allowedExtension 上传文件类型
     * @return 返回上传成功的文件名
     * @throws FileSizeLimitExceededException       如果超出最大大小
     * @throws FileNameLengthLimitExceededException 文件名太长
     * @throws IOException                          比如读写文件出错时
     * @throws InvalidExtensionException            文件校验异常
     */
    public static final String upload(String baseDir, MultipartFile file, String[] allowedExtension)
            throws FileSizeLimitExceededException, IOException, FileNameLengthLimitExceededException,
            InvalidExtensionException {
        int fileNameLength = file.getOriginalFilename().length();
        if (fileNameLength > FileUploadUtils.DEFAULT_FILE_NAME_LENGTH) {
            throw new FileNameLengthLimitExceededException(FileUploadUtils.DEFAULT_FILE_NAME_LENGTH);
        }

        assertAllowed(file, allowedExtension);

        String fileName = extractFilename(file);

        String pathFileName = getPathFileName(baseDir, fileName);

        if (WebKit.isOssEnabled()) {
            return uploadOss(file.getBytes(), pathFileName);
        }

        File desc = getAbsoluteFile(baseDir, fileName);
        file.transferTo(desc);
        return pathFileName;
    }

    /**
     * base64转图片文件
     *
     * @param base64    不包含文件头（data:image/png;base64,）
     * @param extension 文件扩展名
     * @return String
     * @throws IOException
     * @author yilabao
     * @date 2021年4月13日
     */
    public static final String upload(String base64, String extension) throws IOException {
        String fileName = generateFilename(extension);
        String baseDir = ProjectConfig.getUploadPath();
        String pathFileName = getPathFileName(baseDir, fileName);

        byte[] decodeByte = Base64.getDecoder().decode(base64);

        for (int i = 0; i < decodeByte.length; ++i) {
            if (decodeByte[i] < 0) {
                decodeByte[i] += 256;
            }
        }

        if (WebKit.isOssEnabled()) {
            return uploadOss(decodeByte, pathFileName);
        }

        OutputStream out = new FileOutputStream(getAbsoluteFile(baseDir, fileName));

        out.write(decodeByte);

        out.flush();
        out.close();

        return pathFileName;
    }

    /**
     * 生成文件名
     *
     * @param extension 文件扩展名
     * @return String
     * @author yilabao
     * @date 2021年4月13日
     */
    public static final String generateFilename(String extension) {
        return DateUtils.datePath() + "/" + IdUtils.fastUuid() + "." + extension;
    }

    /**
     * 编码文件名
     */
    public static final String extractFilename(MultipartFile file) {
        String extension = getExtension(file);
        return generateFilename(extension);
    }

    private static final File getAbsoluteFile(String uploadDir, String fileName) throws IOException {
        File desc = new File(uploadDir + File.separator + fileName);

        if (!desc.getParentFile().exists()) {
            desc.getParentFile().mkdirs();
        }
        if (!desc.exists()) {
            desc.createNewFile();
        }
        return desc;
    }

    private static final String getPathFileName(String uploadDir, String fileName) throws IOException {
        int dirLastIndex = ProjectConfig.getUploadDir().length() + 1;
        String currentDir = StringUtils.substring(uploadDir, dirLastIndex);
        String pathFileName = Constants.RESOURCE_PREFIX + "/" + currentDir + "/" + fileName;
        return pathFileName;
    }

    /**
     * 文件大小校验
     *
     * @param file 上传的文件
     * @return
     * @throws FileSizeLimitExceededException 如果超出最大大小
     * @throws InvalidExtensionException
     */
    public static final void assertAllowed(MultipartFile file, String[] allowedExtension)
            throws FileSizeLimitExceededException, InvalidExtensionException {
        long size = file.getSize();
        if (size > DEFAULT_MAX_SIZE) {
            throw new FileSizeLimitExceededException(DEFAULT_MAX_SIZE / 1024 / 1024);
        }

        String fileName = file.getOriginalFilename();
        String extension = getExtension(file);
        if (allowedExtension != null && !isAllowedExtension(extension, allowedExtension)) {
            if (allowedExtension == MimeTypeUtils.IMAGE_EXTENSION) {
                throw new InvalidExtensionException.InvalidImageExtensionException(allowedExtension, extension,
                        fileName);
            } else if (allowedExtension == MimeTypeUtils.FLASH_EXTENSION) {
                throw new InvalidExtensionException.InvalidFlashExtensionException(allowedExtension, extension,
                        fileName);
            } else if (allowedExtension == MimeTypeUtils.MEDIA_EXTENSION) {
                throw new InvalidExtensionException.InvalidMediaExtensionException(allowedExtension, extension,
                        fileName);
            } else if (allowedExtension == MimeTypeUtils.VIDEO_EXTENSION) {
                throw new InvalidExtensionException.InvalidVideoExtensionException(allowedExtension, extension,
                        fileName);
            } else {
                throw new InvalidExtensionException(allowedExtension, extension, fileName);
            }
        }

    }

    /**
     * 判断MIME类型是否是允许的MIME类型
     *
     * @param extension
     * @param allowedExtension
     * @return
     */
    public static final boolean isAllowedExtension(String extension, String[] allowedExtension) {
        for (String str : allowedExtension) {
            if (str.equalsIgnoreCase(extension)) {
                return true;
            }
        }
        return false;
    }

    /**
     * 获取文件名的后缀
     *
     * @param file 表单文件
     * @return 后缀名
     */
    public static final String getExtension(MultipartFile file) {
        String extension = FilenameUtils.getExtension(file.getOriginalFilename());
        if (StringUtils.isEmpty(extension) && file.getContentType() != null) {
            extension = MimeTypeUtils.getExtension(file.getContentType());
        }
        return extension;
    }

    /**
     * 上传到OSS
     * 
     * @author yilabao
     * @date 2021年8月18日
     * @param data
     * @param pathFileName
     * @return String
     * @throws IOException
     */
    private static String uploadOss(byte[] data, String pathFileName) {
        String path = StringUtils.substringAfter(pathFileName, Constants.RESOURCE_PREFIX);
        return WebKit.getOssService().upload(data, path).getFileName();
    }

}
